For most Americans, losing our sight is far scarier than losing any of our other senses. It even rates higher than losing a limb, our memory, or the ability to speak.

Taking certain precautions, such as wearing sunglasses, eating a balanced diet, and getting an annual eye exam can help prevent common eye diseases and protect your vision. An eye emergency, however, is often an unexpected event and the best way to protect your vision is to immediately contact your eye doctor.

For those emergencies, however, that happen at the most inconvenient times (such as after hours or when you’re backpacking miles away from an eye doctor), it’s useful to be familiar with some common eye emergencies and understand the severity of your symptoms.

7 Common Eye Emergencies

1. Red eye

We’ve all had red eyes at one time or another and often they’re nothing to worry about. Eye allergies and eyelashes are often the culprits. You can easily remedy these causes by taking allergy medication, avoiding the allergen, or by removing the eyelash. If you wear contacts, a dirty or torn lens can also cause irritation and redness. Properly cleaning or replacing the lens is often enough to relieve the discomfort, but if you experience acute pain and light sensitivity, stop wearing your lenses until the symptoms subside. Contact your eye doctor if your symptoms don’t improve within 24 hrs.

In some cases, however, the cause could be a viral or bacterial infection or an autoimmune inflammation that requires further treatment from your eye doctor. If the redness and irritation doesn’t go away within 24hrs, you should make an appointment with your optometrist. If you’re nowhere near an eye doctor, visit the local urgent care. Often lubricating drops are all that’s needed to clear up the issue but without the expertise of a doctor who specializes in eye care, it can be difficult to accurately diagnose your symptoms.

2. Flashers and floaters

Flashers appear as a streak or flash of light across your field of vision and are caused when the vitreous (the fluid that fills your eye) rubs or pulls on your retina. They are sometimes accompanied by a migraine headache. Floaters look more like small specks, squiggly lines, or cobwebs and are caused by cells clumping together inside the vitreous. As we age, it’s more common to see floaters. You’re also more likely to see these floaters if you are nearsighted or have had cataract surgery or inflammation inside the eye.

While flashers and floaters usually aren’t serious, sometimes they’re related to a retinal tear or detachment. If you begin experiencing either, it’s best to see your eye doctor to confirm that they’re not symptoms of a retinal tear or detachment. You should see your eye doctor immediately to prevent permanent vision loss if you experience any of the following symptoms:

A sudden decrease in your vision

An increase in the size and number of floaters

The sudden appearance of flashes

A shadow in the periphery of your vision

A gray curtain or veil moving across your field of vision

3. Changes in vision

As mentioned above, if your vision suddenly decreases or a shadow or gray curtain is suddenly obstructing your field of vision, call your optometrist immediately as you may be experiencing a retinal tear or detachment. Gradual dimming of your vision could be a symptom of a central retinal artery occlusion where a large clot blocks the flow of blood to the eye. In order to prevent permanent vision loss, you need to see an eye doctor immediately.

4. Eye Pain

A burning or stinging sensation is usually due to a foreign object in your eye that has scratched your cornea. First, try rinsing your eye with artificial tears or contact lens solution. (If you’re wearing contacts, immediately remove the lens as there may be something stuck behind it causing the irritation.) If after 20 minutes the pain hasn’t subsided, call your eye doctor immediately.

5. Headache, nausea, blurry vision

If you’re experiencing a boring pain in one eye with a severe headache, haloes around lights, foggy vision, and/or nausea, you need to be seen immediately. You may be experiencing a spike in the intraocular pressure of your eye caused by a disease called narrow angle glaucoma.

6. Chemical injury

If you get any sort of chemical into your eyes, immediately flush them out with clean water (do not use a sharp stream of water as this may further damage your eye). You can also use contact lens solution or artificial tears. Flush your eyes for a half hour to ensure you rinse out as much of the chemical as possible and then call your optometrist for next steps. If you know what kind of chemical came in contact with your eye, your eye doctor may be able to provide medical advice over the phone. Sometimes flushing is sufficient, but other times, you may need further treatment to prevent vision loss.

7. Physical injury

If you’re ever struck in the eye area, call your optometrist for medical advice. Your eye doctor will want to know if you were hit in the eye itself or only on the orbital plate—the bone surrounding the eye socket. If your eyeball was directly hit, you should be seen immediately as there’s a high chance of a retinal tear or corneal abrasion. If you work in an environment where debris is likely to fly into your eye, we recommend wearing safety goggles to prevent serious injury or discomfort. When playing high impact sports it’s also important to wear a helmet to protect your orbital plate.

If in doubt, always call your optometrist

It’s always safest to talk to your optometrist if you’re experiencing any of the above symptoms. Eye injuries are always treated on a case by case basis and no diagnosis is exactly the same.

Plan ahead when traveling

When you’re traveling, always locate the nearest optometrist as soon as possible so that you know who to call should you experience an eye emergency. An optometrist will always be able to provide the most specialized care for any vision-related issues, but if there isn’t an eye doctor nearby, urgent care can also help treat the injury.

When you go backpacking or travel in any other capacity that puts you far away from medical facilities, plan ahead. Pack lubricating drops, any necessary eye allergy medication, and wear wraparound sunglasses to keep foreign objects out of your eyes and help prevent a physical eye injury.